Mr Carlson's Lab
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A New Circuit Release For Patrons! The Concept.
🕑 Added 2025-08-03 00:58:59 +0000 UTCA very neat circuit is being developed to help with circuit troubleshooting, here are the details!! Enjoy!
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Comments
Jack Lewis
When will we see the Ultra probe. Merry Christmas
Jack Lewis
Thru Hole please!
Nigel C Trueman
Looks like a great tool to have in the toolbox. All my components in stock are through-hole but happy with either.
Michael in Florida
Thank you for telling me not to quick jumper parallel caps. It was just a thought. I acquired an old Eico 150 signal tracer. Replaced all the capacitors & the higher measured resistors outside their tolerances. Replaced all the old side insert pin inputs to banana style, plus a BNC connector for the main input. Turning it on I hear a line voltage hum, a much louder hum when selecting RF input. I also noticed what seems like light solid state component noise too within the hum. Very frustrated trying to find the problem since it seems like two problems with only four operating transistors. Tapping, heating, or resoldering components does nothing. It is working for if I bring a metal screwdriver near the RF input area the hum seriously increases. I know you’re not able to troubleshoot my problem from where you are but maybe you could tell me how you would approach it? The main rectified operating voltage shown in the schematic is negative in relation to the chassis. So the usual bands of capacitor polarity are not to the chassis. It’s beating me up! Two problems in this device…. A slight crackling bacon like noise under a loud hum… Would you…. Just add more capacitance to the power supply? Remove each replaced component one by one to check each one for possible noise? Remove and swap out all four transistors even if working? Something else? Just a thought to ask you about it, but I’ll understand if you don’t reply. I know you are super busy. You are just so knowledgeable. I wonder off camera if you ever get so frustrated that you simply desolder everything and walk away? I just hate giving up…. especially if I’m learning something from it. Should I walk? Your New Friend, Michael in Florida
Mr Carlson's Lab
Hi Michael. No, you can't just jumper a cap into a live circuit. The capacitor that's being jumpered in draws very heavy current immediately, and this damages the supply.
Michael in Florida
Through hole. Question: Without your Add-a-cap circuit, Couldn’t you simply attach jumper cables to a capacitor on the bench…. Then touch it in parallel with the existing cap in the circuit? Just then listen for any reduced hum in real time? Of course being careful with high voltage and using good thick jumper leads with quality clips. Always excellent seeing anything you do. Thank you Mr. Carlson.
Ben Lindvall
Would this be exclusive to power supply hum or would it possibly be useful when designing audio stages for pre amps and so on?
Billy Sharp
Wow this is amazing project.
Bettina Neumeyer
If the design is not that big, I say SMD and through hole. if it is big then go for SMD
Tony Vassil
I would prefer "through hole" for this project. This would make it easier to handle the components. SMD components are so small that they are hard to handle and see.
